<!--
    number 页码。页码从1开始，如：1，2，3，4，5，...
    offset 页码偏移量。如果页码是从0开始，则偏移量为-1；如果页码从1开始，偏移量为0
    totalPages 分页后，页的总数量。
    url URL地址。形如：/c , /c?id=1, /c/b?id=1&limit=10。

    1,会自动向url中添加页码，如：/c?id=1&page=1, /c/b?id=1&limit=10&page=1
    2,当超过totalPages>maxButtons时，会显示...代替多余的按钮
    3,maxButtons>=floatButtons*2
-->
<ul class="pagination" th:fragment="page_pager(number, offset, totalPages, url)" th:with="maxButtons=10,floatButtons=5" xmlns:th="http://www.thymeleaf.org">
    <!-- 上一页 -->
    <li th:if="${number == 1}"><span>上一页</span></li>
    <li th:if="${number > 1}"><a th:href="@{${url}(pageNum=${number+offset-1})}">上一页</a></li>

    <!-- 首页 -->
    <li th:if="${number == 1}" class="active"><span>1</span></li>
    <li th:if="${number > 1}"><a th:href="@{${url}(pageNum=${1+offset})}">1</a></li>

    <th:block th:if="${totalPages>2 && totalPages<=maxButtons}" th:each="i : ${#numbers.sequence(2,totalPages-1)}">
        <li th:if="${number == i}" class="active"><span th:text="${i}">页码</span></li>
        <li th:if="${number != i}"><a th:href="@{${url}(pageNum=${i+offset})}" th:text="${i}">页码</a></li>
    </th:block>

    <th:block th:if="${totalPages > maxButtons}">
        <th:block th:if="${(number-(floatButtons/2)) <= 2}" th:each="i : ${#numbers.sequence(2,2+floatButtons-1)}">
            <li th:if="${number == i}" class="active"><span th:text="${i}">页码</span></li>
            <li th:if="${number != i}"><a th:href="@{${url}(pageNum=${i+offset})}" th:text="${i}">页码</a></li>
        </th:block>
        <!-- ... -->
        <li th:if="${(number-(floatButtons/2))>2}"><span>...</span></li>

        <th:block th:if="${((number-(floatButtons/2))>2) && ((number+(floatButtons/2)-(floatButtons%2==0?1:0)) < (totalPages-1))}"
                  th:each="i : ${#numbers.sequence(number-(floatButtons/2),number+(floatButtons/2)-(floatButtons%2==0?1:0))}">
            <li th:if="${number == i}" class="active"><span th:text="${i}">页码</span></li>
            <li th:if="${number != i}"><a th:href="@{${url}(pageNum=${i+offset})}" th:text="${i}">页码</a></li>
        </th:block>

        <!-- ... -->
        <li th:if="${(number+(floatButtons/2)-(floatButtons%2==0?1:0)) < (totalPages-1)}"><span>...</span></li>
        <th:block th:if="${(number+(floatButtons/2)-(floatButtons%2==0?1:0)) >= (totalPages-1)}" th:each="i : ${#numbers.sequence(totalPages-floatButtons,totalPages-1)}">
            <li th:if="${number == i}" class="active"><span th:text="${i}">页码</span></li>
            <li th:if="${number != i}"><a th:href="@{${url}(pageNum=${i+offset})}" th:text="${i}">页码</a></li>
        </th:block>
    </th:block>

    <!-- 最后一页 -->
    <li th:if="${totalPages>1 && number == totalPages}" class="active"><span th:text="${totalPages}">页码</span></li>
    <li th:if="${totalPages>1 && number != totalPages}"><a th:href="@{${url}(pageNum=${totalPages+offset})}" th:text="${totalPages}">页码</a></li>

    <!-- 下一页 -->
    <li th:if="${number >= totalPages}"><span>下一页</span></li>
    <li th:if="${number < totalPages}"><a th:href="@{${url}(pageNum=${number+offset+1})}">下一页</a></li>
</ul>